A microelectromechanical system device

Abstract

The utility model provides a kind of micro electro mechanical system device, micro electro mechanical system device includes: oppositely arranged mass block, mass block includes movable structure and fixed structure, the movement direction of movable structure is first direction;Interdigital electrode, interdigital electrode is stacked along first direction between movable structure and fixed structure, and it is alternatively fixed in movable structure and fixed structure;First stop piece and second stop piece, first stop piece is located on one side mass block, second stop piece is correspondingly located on the other side mass block, first stop piece has first abutment, first abutment protrudes to first direction, for abutting with second stop piece;The surface of first abutment is set as camber surface.The utility model solves the problem that existing interdigital electrode is still easy to adhere even to collide and break when interdigital electrode moves.

Description

Technical Field

[0001] This utility model relates to the field of microelectromechanical systems (MEMS) technology, and more specifically, to a MEMS device. Background Technology

[0002] Microelectromechanical systems (MEMS) devices typically include movable structures whose range of motion needs to be precisely limited to prevent collisions between interdigital fingers that could lead to mechanical damage or functional failure. In related technologies, protrusions are usually placed on adjacent interdigital fingers. When the movable structure moves the interdigital fingers, the protrusions on the fingers preferentially collide, thus preventing the interdigital fingers from sticking together and achieving a limiting function. However, this protrusion structure cannot achieve complete limiting; under severe motion or overload conditions, surface adhesion can still occur between the interdigital fingers, seriously affecting device reliability. Utility Model Content

[0003] The problem solved by this invention is that the surfaces of the interdigitated fingers stick together under conditions of violent movement or overload, which seriously affects the reliability of the device.

[0004] To address the aforementioned problems, this utility model provides a microelectromechanical system (MEMS) device, comprising: a mass block arranged opposite to each other, the mass block including a movable structure and a fixed structure, the movable structure moving in a first direction; interdigitated electrodes stacked between the movable structure and the fixed structure along the first direction, and alternately fixed to the movable structure and the fixed structure; a first stop and a second stop, the first stop being disposed on one side of the mass block and the second stop being disposed on the other side of the mass block, the first stop having a first abutting portion protruding in the first direction for abutting against the second stop; the surface of the first abutting portion being an arc surface.

[0005] The technical effects achieved by adopting this solution are as follows: The movable structure moves relative to each other along the first direction, allowing the interdigitated electrodes to move closer or further apart. The interdigitated electrodes can sense the displacement of the movable structure in the first direction. By setting a first stop and a second stop on the mass block in the direction of movement of the interdigitated electrodes, they collide with each other before the interdigitated electrodes, effectively limiting the range of movement of the movable structure and preventing the interdigitated electrodes from contacting each other, thus avoiding breakage or surface adhesion. The arc-shaped surface design significantly reduces the contact area between the first stop and the second stop, further reducing the risk of surface adhesion, while improving the uniformity of stress distribution at the contact point and enhancing durability.

[0006] Furthermore, the second stop has a second abutting portion, which abuts against the first abutting portion.

[0007] The technical effect achieved by adopting this technical solution is that the second abutment can prevent the second stop from directly contacting the first abutment and prevent the contact surface on the second stop from directly adhering to the first abutment, thereby improving the service life of the second stop.

[0008] Furthermore, the first abutting part is provided at the end of the first stop member, and the second abutting part is provided at the end of the second stop member.

[0009] The technical effects achieved by adopting this technical solution are as follows: By positioning the first and second abutting portions at the end positions, the force-bearing positions of the first and second stop members are at their ends. Furthermore, in the orthogonal direction of the first direction, the main body dimensions of the first and second stop members can be significantly larger than the dimensions of the first and second abutting portions. Therefore, the main body dimensions of the first and second stop members can have better elastic buffering effects, and their main body dimensions are less prone to breakage.

[0010] Furthermore, the end of the first stop is located between the ends of the two second stops.

[0011] The technical effect achieved by adopting this technical solution is as follows: when the movable structure moves back and forth along the first direction, the end of the first stop can be blocked by the end of a second stop, which realizes the front and rear limit of the movable structure in the first direction, and either side of the interdigital electrode can avoid collision or adhesion with another adjacent interdigital electrode.

[0012] Furthermore, the mass block includes: a moving arm and a stop arm; interdigitated electrodes are connected to the moving arm; one end of the moving arm is fixedly connected to the stop arm; the other end of the moving arm faces the stop arm of another mass block.

[0013] The technical effect achieved by adopting this technical solution is as follows: Under the action of external force, the moving arm and the stop arm of the mass block are integrated into one structure. The length direction of the moving arm is the same as the first direction and is used to set multiple interdigitated electrodes. The length direction of the stop arm is orthogonal to the first direction and is used to limit the moving arm of another mass block. This can prevent the interdigitated electrodes on the two mass blocks from colliding and contacting each other under a strong impact in the first direction, which would lead to device failure.

[0014] Furthermore, a limiting element is provided at one end of the moving arm facing the stop arm of the other mass block, and a limiting groove is provided on the stop arm of the other mass block.

[0015] The technical effects achieved by adopting this technical solution are as follows: the limiting member is flexible in the first direction and in the orthogonal direction of the first direction. When the movable structure moves along the first direction, the limiting groove is used to limit the limiting member in the first direction and in the orthogonal direction of the first direction. On the one hand, when the inertial force of the moving arm in the first direction is too high, the side of the limiting groove opposite to the limiting member abuts against the limiting member to provide an elastic buffering effect. On the other hand, when the distance between any moving arm and the other stop arm is at its maximum or minimum value, the limiting member is always at least partially located in the limiting groove, thereby always achieving limitation in the orthogonal direction of the first direction, preventing the movable structure from deviating from the first direction, or even causing the interdigitated electrode to come into contact with the other moving arm directly opposite it and be damaged.

[0016] Furthermore, the end of the limiting member has a first arc-shaped protrusion.

[0017] The technical effects achieved by adopting this technical solution are as follows: The first arc protrusion is used to achieve point contact between the limiting component and the inner wall of the limiting groove, thereby reducing the contact area and avoiding adhesion or excessive end wear caused by a large contact area.

[0018] Furthermore, the side of the limiting groove opposite to the limiting member has a second arc protrusion.

[0019] The technical effects achieved by adopting this technical solution are as follows: the inner wall of the limiting component and the limiting groove achieves contact between the arc and the surface, or between the arcs, which not only reduces the contact area but also improves the mechanical properties of the contact and prevents local wear or adhesion caused by surface-to-surface contact.

[0020] Furthermore, the first stop and the first abutment are an integral structure.

[0021] The technical effects achieved by adopting this technical solution are as follows: the first stop and the first abutment can be integrally formed, for example, through the same deposition process and the same etching process, thus resulting in higher processing efficiency. At the same time, their integration is stronger, and the first stop and the first abutment are less likely to break when the first abutment and the second abutment impact each other.

[0022] In summary, the above-mentioned technical solutions of this application can have one or more of the following advantages or beneficial effects: I) By setting the first stop and the second stop in the movement direction of the interdigital electrodes, so that they collide with each other before the interdigital electrodes, the movement range of the movable structure is effectively limited, and the interdigital electrodes are prevented from contacting each other, resulting in breakage or surface adhesion; II) The arc surface design significantly reduces the contact area between the first stop and the second stop, further reducing the risk of surface adhesion, while improving the uniformity of stress distribution at the contact point and enhancing durability; III) The limiting member is flexible in the first direction and the orthogonal direction of the first direction, and when the movable structure moves along the first direction, the limiting groove is used to limit the limiting member in the first direction and the orthogonal direction of the first direction. Attached Figure Description

[0023] Figure 1 A schematic diagram of the structure of a microelectromechanical system device provided in an embodiment of this utility model; Figure 2 for Figure 1 A magnified view of a portion of region A in the middle; Figure 3 for Figure 1 A magnified view of a portion of region B in the middle.

[0024] Explanation of reference numerals in the attached figures: 100 - Microelectromechanical system device; 110 - Mass block; 111 - Moving arm; 112 - Stop arm; 113 - Limiting groove; 114 - Limiting element; 115 - First arc protrusion; 116 - Second arc protrusion; 120 - Interdigitated electrode; 130 - First stop element; 131 - First abutment part; 140 - Second stop element; 141 - Second abutment part. Detailed Implementation

[0025] The purpose of this invention is to provide a microelectromechanical system device for limiting the range of motion of movable structures and preventing interdigitated electrodes from coming into contact with each other, which could lead to breakage or surface adhesion.

[0026] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings.

[0027] See Figures 1-3This utility model provides a microelectromechanical system (MEMS) device 100, which includes: a mass block 110 disposed opposite to each other, the mass block 110 including a movable structure and a fixed structure, the movable structure moving in a first direction; interdigitated electrodes 120 stacked between the movable structure and the fixed structure along the first direction and alternately fixed to the movable structure and the fixed structure; a first stop 130 and a second stop 140, the first stop 130 being disposed on one side of the mass block 110 and the second stop 140 being disposed on the other side of the mass block 110, the first stop 130 having a first abutment portion 131 protruding in the first direction for abutting against the second stop 140; the surface of the first abutment portion 131 being an arc surface.

[0028] In this embodiment, the movable structure moves relative to each other along a first direction, allowing the interdigital electrodes 120 to move closer or further apart. The interdigital electrodes 120 can sense the displacement of the movable structure in the first direction. By providing a first stop 130 and a second stop 140 on the mass block 110 in the direction of movement of the interdigital electrodes 120, the collision occurs before the interdigital electrodes, effectively limiting the range of movement of the movable structure and preventing the interdigital electrodes 120 from contacting each other, thus avoiding breakage or surface adhesion. The arc surface design significantly reduces the contact area between the first stop 130 and the second stop 140, further reducing the risk of surface adhesion, while improving the uniformity of stress distribution at the contact point and enhancing durability.

[0029] In one specific embodiment, the first stop 130 and the second stop 140 are located before or after a plurality of consecutive interdigital electrodes 120, such that the first stop 130 and the second stop 140 do not affect the electrical signal between the interdigital electrodes 120.

[0030] Preferably, at least two sets of the first stop 130 and the second stop 140 are provided, located before and after the consecutive interdigitated electrodes 120. Furthermore, the two sets of stops are symmetrical about the central interdigitated electrodes 120, meaning that each mass block 110 is provided with a first stop 130 and a second stop 140, respectively corresponding to the second stop 140 and the first stop 130 on another mass block 110, ensuring that each mass block 110 is force-balanced and less prone to deflection relative to the first direction.

[0031] In one specific embodiment, the length directions of the first stop 130 and the second stop 140 are orthogonal to the first direction.

[0032] In one specific embodiment, the second stop 140 has a second abutting portion 141, which abuts against the first abutting portion 131.

[0033] Correspondingly, the second contact portion 141 protrudes in the first direction.

[0034] It should be noted that the second abutment portion 141 can prevent the second stop member 140 from directly contacting the first abutment portion 131 and prevent the contact surface on the second stop member 140 from directly adhering to the first abutment portion 131, thereby improving the service life of the second stop member 140.

[0035] Preferably, the surface of the second abutment portion 141 is an arc surface. It can be understood that having only the second abutment portion 141 an arc surface has a similar effect to having only the first abutment portion 131 an arc surface. Furthermore, having both the second abutment portion 141 and the first abutment portion 131 an arc surface allows for contact between the first stop member 130 and the second stop member 140 using two arc surfaces, further improving their durability.

[0036] In one specific embodiment, the first abutting portion 131 is provided at the end of the first stop member 130, and the second abutting portion 141 is provided at the end of the second stop member 140.

[0037] It should be noted that by positioning the first abutment portion 131 and the second abutment portion 141 at the end positions, the force-bearing positions of the first stop member 130 and the second stop member 140 are at their ends. Furthermore, in the orthogonal direction of the first direction, the main body dimensions of the first stop member 130 and the second stop member 140 can be significantly larger than the dimensions of the first abutment portion 131 and the second abutment portion 141. Therefore, the main body dimensions of the first stop member 130 and the second stop member 140 can have better elastic cushioning effects and are less prone to breakage.

[0038] In one specific embodiment, the end of the first stop 130 is located between the ends of the two second stops 140.

[0039] It should be noted that when the movable structure moves back and forth along the first direction, the end of the first stop 130 can be blocked by the end of a second stop 140, thus achieving the front and rear limit of the movable structure in the first direction. Either side of the interdigital electrode 120 can avoid collision or adhesion with another adjacent interdigital electrode 120.

[0040] In one specific embodiment, the mass block 110 includes: a movable arm 111 and a stop arm 112; an interdigitated electrode 120 is connected to the movable arm 111; one end of the movable arm 111 is fixedly connected to the stop arm 112; the other end of the movable arm 111 faces the stop arm 112 of another mass block 110.

[0041] Furthermore, the interdigitated electrode 120 is connected to the inner side of the movable arm 111, that is, the opposite side of the two movable arms 111. The inner side of the movable arm 111 is provided with a first stop 130, an interdigitated electrode 120 and a second stop 140 in sequence along the first direction, so that the middle interdigitated electrode 120 can be kept in balance.

[0042] It should be noted that, under the action of external force, the moving arm 111 and the stop arm 112 of the mass block 110 are an integral structure. The length direction of the moving arm 111 is the same as the first direction and is used to set multiple interdigital electrodes 120. The length direction of the stop arm 112 is orthogonal to the first direction. The stop arm 112 is used to limit the moving arm 111 of the mass block 110, which can prevent the interdigital electrodes 120 on the two mass blocks 110 from colliding and contacting each other under a strong impact in the first direction, thus preventing device failure.

[0043] In one specific embodiment, a limiting member 114 is provided at one end of the moving arm 111 facing the stop arm 112 of the other mass block 110, and a limiting groove 113 is provided on the stop arm 112 of the other mass block 110.

[0044] The limiting member 114 can be a strip extending along the first direction.

[0045] It should be noted that the limiting member 114 is flexible in the first direction and in the orthogonal direction of the first direction. When the movable structure moves along the first direction, the limiting groove 113 is used to limit the limiting member 114 in the first direction and in the orthogonal direction of the first direction.

[0046] On the one hand, when the inertial force of the moving arm 111 in the first direction is too high, the side of the limiting groove 113 opposite to the limiting member 114 abuts against the limiting member 114 to provide an elastic buffering effect.

[0047] On the other hand, when the distance between any moving arm 111 and the other stop arm 112 is at its maximum or minimum value, the limiting member 114 is always at least partially located in the limiting groove 113, so that it can always be limited in the orthogonal direction of the first direction, avoiding the movable structure from deviating from the first direction, or even causing the interdigitated electrode 120 to come into contact with the other moving arm 111 directly opposite it and be damaged.

[0048] In one specific embodiment, the end of the limiting member 114 has a first arcuate protrusion 115.

[0049] It should be noted that the first arc protrusion 115 is used to achieve point contact between the limiting member 114 and the inner wall of the limiting groove 113, thereby reducing the contact area and avoiding adhesion or excessive end wear caused by a large contact area.

[0050] In one specific embodiment, the side of the limiting groove 113 opposite to the limiting member 114 has a second arc protrusion 116.

[0051] It should be noted that the inner walls of the limiting member 114 and the limiting groove 113 achieve contact between the arc and the surface, or between the arcs, which not only reduces the contact area but also improves the mechanical properties of the contact, preventing local wear or adhesion caused by surface-to-surface contact.

[0052] In one specific embodiment, the first stop 130 and the first abutting part 131 are an integral structure.

[0053] It should be noted that the first stop 130 and the first abutment portion 131 can be integrally formed, for example, through the same deposition process and the same etching process, thus resulting in higher processing efficiency. At the same time, their integration is stronger, and the first stop 130 and the first abutment portion 131 are less likely to break when the first abutment portion 131 and the second abutment portion 141 impact each other.

[0054] Preferably, the first stop 130, the first abutment 131, and the interdigitated electrode 120 are all integrally formed from the same material, thus achieving better process efficiency in deposition and etching processes. It is understood that the second stop 140 and the second abutment 141 can also be made of the same material and integrally formed with the interdigitated electrode 120.

[0055] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A microelectromechanical system device, characterized by The microelectromechanical system (MEMS) devices include: The mass block (110) is set relative to each other. The mass block (110) includes a movable structure and a fixed structure. The direction of movement of the movable structure is a first direction. Interdigitated electrodes (120) are stacked between the movable structure and the fixed structure along the first direction and are alternately fixed to the movable structure and the fixed structure; A first stop (130) and a second stop (140) are provided. The first stop (130) is disposed on one side of the mass block (110), and the second stop (140) is disposed on the other side of the mass block (110). The first stop (130) has a first abutting part (131) which protrudes in the first direction and is used to abut against the second stop (140). The surface of the first contact part (131) is set as an arc surface.

2. The microelectromechanical system device of claim 1, wherein, The second stop (140) has a second abutting portion (141) for abutting against the first abutting portion (131).

3. The microelectromechanical system device according to claim 2, characterized in that, The first abutting part (131) is provided at the end of the first stop (130), and the second abutting part (141) is provided at the end of the second stop (140).

4. The microelectromechanical system device of claim 3, wherein, The end of the first stop (130) is located between the ends of the two second stops (140).

5. The microelectromechanical system device of claim 1, wherein, The mass block (110) includes: A movable arm (111) and a stop arm (112); the interdigitated electrode (120) is connected to the movable arm (111); one end of the movable arm (111) is fixedly connected to the stop arm (112); the other end of the movable arm (111) is directed toward the stop arm (112) of another mass block (110).

6. The microelectromechanical system device according to claim 5, characterized in that, The moving arm (111) is provided with a limiting member (114) at one end of the stop arm (112) of the other mass block (110), and a limiting groove (113) is provided on the stop arm (112) of the other mass block (110).

7. The microelectromechanical system device of claim 6, wherein The end of the limiting member (114) has a first arc protrusion (115).

8. The microelectromechanical system device of claim 6, wherein, The limiting groove (113) has a second arc protrusion (116) on the side opposite to the limiting member (114).

9. The microelectromechanical system device of claim 1, wherein, The first stop (130) and the first abutment (131) are an integral structure.

Images